1. Technical Field
This invention relates to labels and in particular to labels for ovenable products.
2. Description of the Related Art
Various types of promotional items are used for marketing consumer products. One common technique is to attach the promotional items directly to the products or product packaging. The promotional items can be adhesive backed labels that are either removable or have tear-away panels. These labels can be, for example, coupons that consumers can peel off the product or peel-off tokens or entry forms for a promotional game or giveaway.
Some such labels have multiple layers releasably adhered together. For example, U.S. Pat. No. 4,479,838, hereby incorporated by reference as though fully set forth herein, defines a multiple ply label construction with a transparent base sheet to which is releasably adhered a non-transparent top sheet printed to define a coupon, for example. These two layers are adhered to a release liner. Such a label is used by peeling the base sheet (with the top sheet attached) from the release liner and adhering it to a product. The top sheet can later be removed from the base sheet, for example when the purchaser of the product redeems the coupon.
These labels are often made and applied using automated line processes. Thus, large quantities of labels are formed in a single file line of labels on a continuous backing web that is either wound or folded, for example, in a Z-fold configuration. Individual labels can be cut from the web and applied to the products or stacked for storage or transport.
Some products, such as some frozen pizzas or packaged meals (“TV dinners”), are designed to be heated in a conventional oven or a microwave oven while in some or all of the product packaging. Such “ovenable” packages or containers, for example, are disclosed in U.S. Pat. Nos. 4,449,633; 4,836,438; 4,866,786; 5,565,228; and 6,307,192, the disclosures of which are hereby incorporated by reference herein. Such ovenable packages can be disposable trays, pans or other containers made of paper, aluminum foil, plastic or other materials capable of sustaining the heat from conventional, convection or microwave ovens, which produce heat typically in the range of 350-500° F. The use of the packaging in such high heat environments presents a problem for marketers in that conventional labels may break down in some way, for example they may melt or be singed by the heat, which can distort, discolor or otherwise obscure the print on the label. Or, the adhesive may fail from the high heat causing the label to separate from the package while it is cooking. Thus, a high temperature label is needed.